DE 10 2010 026 780 A1 describes a method for measuring a temperature with contactless transmission of energy. With the contactless transmission of energy for charging a battery of a motor vehicle between a receiver for receiving the energy and a transmitter for transmitting the energy, the temperature is measured in the area between the transmitter and the receiver.
WO 2010/116566 A1 describes an inductive power supply device. In this case, freezing is monitored by means of a movable coil of the inductive power supply device.
DE 10 2011 076 186 A1 describes a charging device for inductive charging of an electrical energy store of a motor vehicle. The charging device comprises a primary coil, which is designed to induce a voltage in a secondary coil of the motor vehicle for charging the electrical energy store. The charging device comprises in addition also a lifting mechanism, which is designed to move the primary coil between a stored position and a charging position. The primary coil is in this case arranged in a ground induction plate which can be moved by means of a lifting mechanism. The ground induction plate can be pivoted or shaken by the lifting mechanism in order to get rid of animals, leaves or other objects, or to remove moisture, at least partially, from the upper surface of the ground induction plate which is facing a bottom surface of the motor vehicle during the charging operation.
In the case of these types of charging devices that are provided with a lifting mechanism, problems can occur when the temperatures are at or below the freezing point and in particular under the conditions of humid weather, wherein the moisture on the lifting mechanism can cause problems of the lifting mechanism. In particular when movable parts of the lifting mechanism freeze, such as for example joints, movable struts, bellows or the like, a problem-free activation of the lifting mechanism may be restricted or even prevented. The efficiency during inductive charging of an energy storage device of a motor vehicle can thus be significantly limited, or the charging process as such may not be even possible under certain conditions because the primary coil may no longer be moved if the lifting mechanism is frozen to the charging position, in which the gap between the primary coil and the secondary coil should be as small as possible.